Drug target and construct for Japanese encephalitis virus infection

Abstract

A group of mosquito-borne flaviviruses that cause fatal encephalitis in humans is among the most important of all emerging human pathogens of global significance. This group includes Japanese encephalitis virus (JEV), West Nile virus, St. Louis encephalitis virus, and Murray Valley encephalitis virus. In the present disclosure, the first reverse genetics system has been developed for SA14-14-2, a live JE vaccine that is most commonly used in most JE-endemic areas, by constructing an infectious bacterial artificial chromosome that contains the full-length SA14-14-2 cDNA. Using this infectious SA 14-14-2 cDNA, combined with a mouse model for JEV infection, a key viral neurovirulence factor has been discovered that is a conserved single amino acid in the ij hairpin adjacent to the fusion loop of the viral E glycoprotein, which regulates viral infectivity into neurons within the central nervous system.

What is claimed is: 
     
       1. A DNA construct comprising a cDNA sequence that encodes a JEV genomic RNA and has a nucleotide sequence set forth in SEQ ID NO:1 or SEQ ID NO:32;
 wherein the DNA construct comprises a nucleotide sequence set forth in SEQ ID NO:2 when the cDNA sequence has the nucleotide sequence set forth in SEQ ID NO:1, and wherein the DNA construct comprises a nucleotide sequence set forth in SEQ ID NO:33 when the cDNA sequence has the nucleotide sequence set forth in SEQ ID NO:32. 
 
     
     
       2. The DNA construct of  claim 1 , further comprising a bacterial artificial chromosome. 
     
     
       3. The DNA construct of  claim 1 , wherein the DNA construct consists of the nucleotide sequence set forth in SEQ ID NO:2 or SEQ ID NO:33. 
     
     
       4. A DNA construct comprising a nucleic acid sequence that encodes a JEV genomic RNA and has at least about 70% identity to a nucleotide sequence as set forth in SEQ ID NO:4, SEQ ID NO:5, SEQ ID NO:6, SEQ ID NO:7, SEQ ID NO:8, SEQ ID NO:9, SEQ ID NO:10, SEQ ID NO:11, SEQ ID NO:12, SEQ ID NO:13, SEQ ID NO:14, SEQ ID NO:15, SEQ ID NO:16, or SEQ ID NO:17;
 wherein the nucleic acid sequence is the nucleotide sequence as set forth in SEQ ID NO:4, SEQ ID NO:5, SEQ ID NO:6, SEQ ID NO:7, SEQ ID NO:8, SEQ ID NO:9, SEQ ID NO:10, SEQ ID NO:11, SEQ ID NO:12, SEQ ID NO:13, SEQ ID NO:14, SEQ ID NO:15, SEQ ID NO:16, or SEQ ID NO:17. 
 
     
     
       5. A vector comprising the DNA construct of  claim 1 .